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Fahrenheit to Celsius Converter

Convert °F to °C instantly, with a reference table covering weather, fever thresholds and oven temperatures.

Fahrenheit to Celsius Converter

1 °F = -17.22 °C

Multiply degrees Fahrenheit by 0.5556, then add -17.77777777777778, to get degrees Celsius.

The link carries the values you entered, so whoever opens it sees the same result. Nothing is stored on our side — the numbers travel in the link itself.

Degrees Fahrenheit to degrees Celsius reference table

The conversions people look up most often, rounded to 2 decimal places.

Common degrees Fahrenheit to degrees Celsius conversions
Degree Fahrenheit (°F)Degree Celsius (°C)
-40 °F-40 °C
0 °F-17.78 °C
32 °F0 °C
50 °F10 °C
68 °F20 °C
72 °F22.22 °C
90 °F32.22 °C
98.6 °F37 °C
100.4 °F38 °C
212 °F100 °C
350 °F176.67 °C
400 °F204.44 °C
450 °F232.22 °C

How the fahrenheit to celsius converter calculation works

Two scales with different zero points and different step sizes, so this needs two operations rather than one:

°C = (°F − 32) × 5/9

Order matters. Subtract the 32 first, then multiply. Doing it the other way round gives an answer that is wrong by about 18 degrees — enough to turn a fever into a normal temperature.

Working through the numbers people actually look up:

Weather. 72°F, the American thermostat default, is (72 − 32) × 5/9 = 22.2°C. A 90°F summer day is 32.2°C, and 0°F — cold but not extraordinary in the northern US — is −17.8°C.

Fever. Normal body temperature of 98.6°F is 37.0°C. The clinical fever threshold of 100.4°F is exactly 38.0°C — that oddly specific Fahrenheit number exists because the underlying definition is the round Celsius one.

Cooking. A 350°F oven is 176.7°C, which European recipes give as 180°C. 400°F is 204.4°C (written as 200°C), and 450°F is 232.2°C (230°C). The rounding is always to the nearest 10°C, so converted oven temperatures are approximate by convention rather than by accident.

Two anchors worth keeping:

  • −40 is identical in both scales. The only crossing point, and a quick check that a formula is the right way round.
  • Subtract 30 and halve for a rough figure: 72 → 42 → 21, against a true 22.2. Good for weather, not for medicine or meat.

For a temperature difference rather than a temperature, multiply by 5/9 and skip the 32 entirely.

Frequently asked questions

How do I convert degrees Fahrenheit to degrees Celsius?

Multiply the Celsius temperature by 9/5 (1.8), then add 32.

How many degrees Celsius are in 68 °F?

68 °F equals 20.00 °C. The reference table on this page lists the other values people look up most often.

How do I convert degrees Celsius back to degrees Fahrenheit?

Subtract 32 first, then multiply by 5/9. Doing it in the other order gives the wrong answer.

Is this conversion exact?

Yes. The relationship between Celsius and Fahrenheit is defined exactly, so the only imprecision comes from rounding the result.

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